Industrial-scale supercritical fluid extraction (SFE) facilities have been widely used for example, for decaffeination of coffee beans or teas, for removal of undesired substances from cork, for extraction of essential oils from herbaceous plant materials, for concentration of cannabinoids from cannabis, among other commercial uses. Bench-scale supercritical fluid extraction devices are also commercially available. However, laboratory-scale versions of SFE apparatus are too bulky and too heavy to be carried by an individual. The problems associated with the size and scale of even the smallest commercial SFE apparatus are due to the requirement for a pump component or a compressor plus cooling equipment.
There have been attempts to reduce the size of the components required for successful SFE processing. For example, U.S. Pat. Nos. 5,637,209 and 5,237,824 disclosed generation of supercritical carbon dioxide fluid in a generator tank by heating the carbon dioxide to certain temperature in the generator tank, then directing the supercritical carbon dioxide fluid into one or multiple extraction vessels for use in extraction processes. These designs replaced the pump or compressor with a supercritical fluid generator and thus reduced the weight and size of the supercritical fluid extractor to a portable level. However, the problems of bulkiness, excessive weight and size still remain with these smaller scale SFE apparatus.